In metallic solids,the number of atoms for the face-centered and the body-centered cubic unit cells are,respectively:

How many unit cells are present in $39 \ g$ of potassium that crystallizes in a body-centered cubic $(BCC)$ structure? [Atomic weight of $K = 39$]

The number of unit cells present in $39 \ g$ of potassium if it crystallizes as a body-centered cubic $(BCC)$ structure is ($N = \text{Avogadro number}$, $\text{At. wt. of potassium} = 39$).

$A$ binary compound $(A^{+} B^{-})$ has a zinc blende structure where $B^{-}$ ions form the lattice and $A^{+}$ ions occupy $25\%$ of the tetrahedral voids. What is the formula of the compound?

The radius of $Na^{+}$ is $95 \, pm$ and the radius of $Cl^{-}$ ion is $181 \, pm$. What is the coordination number of $Na^{+}$?

Which of the following is a $1:2$ type compound?